Given that frontswap_register_ops must be called from built-in code,
there is no need to handle the case of swapfiles coming online before
or during it, so delete the code that deals with that case.
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
mm/frontswap.c | 41 -----------------------------------------
1 file changed, 41 deletions(-)
diff --git a/mm/frontswap.c b/mm/frontswap.c
index f51159f0d75d5..35040fa4eba83 100644
--- a/mm/frontswap.c
+++ b/mm/frontswap.c
@@ -99,25 +99,6 @@ static inline void inc_frontswap_invalidates(void) { }
*/
void frontswap_register_ops(struct frontswap_ops *ops)
{
- DECLARE_BITMAP(a, MAX_SWAPFILES);
- DECLARE_BITMAP(b, MAX_SWAPFILES);
- struct swap_info_struct *si;
- unsigned int i;
-
- bitmap_zero(a, MAX_SWAPFILES);
- bitmap_zero(b, MAX_SWAPFILES);
-
- spin_lock(&swap_lock);
- plist_for_each_entry(si, &swap_active_head, list) {
- if (!WARN_ON(!si->frontswap_map))
- __set_bit(si->type, a);
- }
- spin_unlock(&swap_lock);
-
- /* the new ops needs to know the currently active swap devices */
- for_each_set_bit(i, a, MAX_SWAPFILES)
- ops->init(i);
-
/*
* Setting frontswap_ops must happen after the ops->init() calls
* above; cmpxchg implies smp_mb() which will ensure the init is
@@ -128,28 +109,6 @@ void frontswap_register_ops(struct frontswap_ops *ops)
} while (cmpxchg(&frontswap_ops, ops->next, ops) != ops->next);
static_branch_inc(&frontswap_enabled_key);
-
- spin_lock(&swap_lock);
- plist_for_each_entry(si, &swap_active_head, list) {
- if (si->frontswap_map)
- __set_bit(si->type, b);
- }
- spin_unlock(&swap_lock);
-
- /*
- * On the very unlikely chance that a swap device was added or
- * removed between setting the "a" list bits and the ops init
- * calls, we re-check and do init or invalidate for any changed
- * bits.
- */
- if (unlikely(!bitmap_equal(a, b, MAX_SWAPFILES))) {
- for (i = 0; i < MAX_SWAPFILES; i++) {
- if (!test_bit(i, a) && test_bit(i, b))
- ops->init(i);
- else if (test_bit(i, a) && !test_bit(i, b))
- ops->invalidate_area(i);
- }
- }
}
/*
--
2.30.2
